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                                                                    EXHIBIT 10.2

                        GUARANTY AND SURETYSHIP AGREEMENT

      THIS GUARANTY AND SURETYSHIP AGREEMENT (this "GUARANTY") dated as of 30th
day of June, 2004, made by BLACK BOX CORPORATION, a Delaware corporation
("GUARANTOR"), to the lenders parties to the Credit Agreement (as defined below)
from time to time (the "LENDERS") and CITIZENS BANK OF PENNSYLVANIA, a banking
association organized under the laws of the Commonwealth of Pennsylvania, as
agent for the Lenders (in such capacity, together with its successors in such
capacity, the "AGENT").

                                   WITNESSETH:

      WHEREAS, Guarantor, the Borrower (as hereinafter defined), certain of the
Lenders, the Agent (through its predecessor in interest, Mellon Bank, N.A.), and
certain Subsidiaries of the Borrower entered into that certain Credit Agreement
dated April 4, 2000, as amended (the "Existing Credit Agreement"), pursuant to
which the Lenders made a revolving credit facility available to the Borrower;

      WHEREAS, in connection with the Existing Credit Agreement, the Guarantor
executed and delivered to the Lenders and the Agent that certain Guaranty and
Suretyship Agreement dated as of April 4, 2000 (the "Existing Guaranty");

      WHEREAS, Guarantor, the Borrower, the Lenders and the Agent are parties to
an Amended and Restated Credit Agreement, dated as of June 30, 2004 (as amended,
the "CREDIT AGREEMENT") which amended and restates the Existing Credit
Agreement; and

      WHEREAS, pursuant to the terms of the Credit Agreement, Lenders may make
certain Loans to Black Box Corporation of Pennsylvania, a Subsidiary of the
Guarantor (the "BORROWER"), as evidenced in part by certain promissory notes of
the Borrower to each Lender dated of even date herewith (collectively, the
"NOTE");

      WHEREAS, the execution and delivery by Guarantor of this Guaranty is a
condition to Lenders' obligation to make Loans to the Borrower and to issue
letters of credit on behalf of the Borrower, and Guarantor, as owner, directly
or indirectly, of all of the outstanding shares of stock of the Borrower,
expects to derive a financial benefit from the making of such Loans and
issuances of such letters of credit; and

      WHEREAS, this Guaranty amends and restates the Existing Guaranty.

      NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt of which is hereby acknowledged by
Guarantor, and intending to be legally bound, Guarantor hereby agrees as
follows:

                                   ARTICLE I.
                                   DEFINITIONS

            1.1   Definitions.

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                  (a)   Certain Definitions. Capitalized terms not otherwise
defined herein shall have the meanings given in the Credit Agreement. In
addition to the other terms defined elsewhere in this Agreement, as used herein
the following terms shall have the following meanings:

                  "Guaranteed Obligations" shall mean all obligations from time
      to time of the Borrower to the Agent or any Lender under or in connection
      with any Loan Document, including all obligations to pay principal,
      interest, fees, indemnities or other amounts under such Loan Documents, in
      each case whether such obligations are direct or indirect, secured or
      unsecured, joint or several, absolute or contingent, due or to become due,
      whether for payment or performance, now existing or hereafter arising
      (including interest and other obligations arising or accruing after the
      commencement of any bankruptcy, insolvency, reorganization, dissolution or
      similar proceeding with respect to the Borrower or any other Person, or
      which would have arisen or accrued but for the commencement of such
      proceeding, even if such obligation or the claim therefor is not
      enforceable or allowable in such proceeding).

                                   ARTICLE II.
                             GUARANTY AND SURETYSHIP

            2.1   Guaranty and Suretyship. The Guarantor hereby absolutely,
unconditionally and irrevocably guarantees and becomes surety for the full and
punctual payment and performance of the Guaranteed Obligations as and when such
payment or performance shall become due (at scheduled maturity, by acceleration
or otherwise) in accordance with the terms of the Loan Documents. This Agreement
is an agreement of suretyship as well as of guaranty, is a guarantee of payment
and performance and not merely of collectibility, and is in no way conditioned
upon any attempt to collect from or proceed against the Borrower or any other
Person or any other event or circumstance. The obligations of the Guarantor
under this Agreement are direct and primary obligations of the Guarantor and are
independent of the Guaranteed Obligations, and a separate action or actions may
be brought against the Guarantor regardless of whether action is brought against
the Borrower or any other Person or whether the Borrower or any other Person is
joined in any such action or actions.

            2.2   Obligations Absolute. The Guarantor agrees that the Guaranteed
Obligations will be paid and performed strictly in accordance with the terms of
the Loan Documents, regardless of any law, regulation or order now or hereafter
in effect in any jurisdiction affecting the Guaranteed Obligations, any of the
terms of the Loan Documents or the rights of the Agent or any Lender or any
other Person with respect thereto. The obligations of the Guarantor under this
Agreement shall be absolute, unconditional and irrevocable, irrespective of any
of the following:

                  (a)   any lack of legality, validity, enforceability,
allowability (in a bankruptcy, insolvency, reorganization, dissolution or
similar proceeding, or otherwise), or any avoidance or subordination, in whole
or in part, of any Loan Document or any of the Guaranteed Obligations;

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                  (b)   any change in the amount, nature, time, place or manner
of payment or performance of, or in any other term of, any of the Guaranteed
Obligations (whether or not such change is contemplated by the Loan Documents as
presently constituted, and specifically including any increase in the Guaranteed
Obligations, whether resulting from the extension of additional credit to the
Borrower or otherwise), any execution of any additional Loan Documents, or any
amendment or waiver of or any consent to departure from any Loan Document;

                  (c)   any taking, exchange, release, impairment or
nonperfection of any collateral, or any taking, release, impairment or amendment
or waiver of or consent to departure from any other guaranty or other direct or
indirect security for any of the Guaranteed Obligations;

                  (d)   any manner of application of collateral or other direct
or indirect security for any of the Guaranteed Obligations, or proceeds thereof,
to any of the Guaranteed Obligations, or any commercially reasonable manner of
sale or other disposition of any collateral for any of the Guaranteed
Obligations or any other assets of the Borrower;

                  (e)   any permanent impairment by any Lender or any other
Person of any recourse of the Guarantor against the Borrower or any other
Person, or any other permanent impairment by any Lender or any other Person of
the suretyship status of the Guarantor;

                  (f)   any bankruptcy, insolvency, reorganization, dissolution
or similar proceedings with respect to, or any change, restructuring or
termination of the corporate structure or existence of, the Borrower, the
Guarantor or any other Person; or

                  (g)   any failure of any Lender or any other Person to
disclose to the Guarantor any information pertaining to the business,
operations, condition (financial or other) or prospects of the Borrower or any
other Person, or to give any other notice, disclosure or demand.

            2.3   Waivers, etc. The Guarantor hereby irrevocably waives any
defense to or limitation on its obligations under this Agreement arising out of
or based upon any matter referred to in Section 2.2 and, without limiting the
generality of the foregoing, any requirement of promptness, diligence or notice
of acceptance, any other notice, disclosure or demand with respect to any of the
Guaranteed Obligations and this Agreement, any requirement of acceptance hereof,
reliance hereon or knowledge hereof by the Agent or any Lender, and any
requirement that the Agent or any Lender protect, secure, perfect or insure any
lien or any property subject thereto or exhaust any right or take any action
against the Borrower or any other Person or any collateral or other direct or
indirect security for any of the Guaranteed Obligations. Notwithstanding the
foregoing sentence, the Guarantor's waiver under this Section 2.3 shall apply
only to the Guarantor's obligations hereunder and shall not limit or waive any
of the Guarantor's rights or obligations as a borrower under the Credit
Agreement or any other subrogation rights.

            2.4   Reinstatement. This Agreement shall continue to be effective,
or be automatically reinstated, as the case may be, if at any time payment of
any of the Guaranteed

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Obligations is avoided, rescinded or must otherwise be returned by the Agent or
any Lender for any reason, all as though such payment had not been made.

            2.5   No Stay. Without limiting the generality of any other
provision of this Agreement, if any acceleration of the time for payment or
performance of any Guaranteed Obligation, or any condition to any such
acceleration, shall at any time be stayed, enjoined or prevented for any reason
(including stay or injunction resulting from the pendency against the Borrower
or any other Person of a bankruptcy, insolvency, reorganization, dissolution or
similar proceeding), the Guarantor agrees that, for purposes of this Agreement
and its obligations hereunder, at the option of the Agent such Guaranteed
Obligation shall be deemed to have been accelerated and such condition to
acceleration shall be deemed to have been met.

            2.6   Payments. All payments to be made by the Guarantor pursuant to
this Agreement shall be made at the times and in the manner prescribed for
payments in Articles II and III of the Credit Agreement, without setoff,
counterclaim, withholding or other deduction of any nature. All payments made by
the Guarantor pursuant to this Agreement may be applied to the Guaranteed
Obligations and all other amounts payable under this Agreement in such order as
the Agent may elect.

            2.7   Subrogation. Etc. Any rights which the Guarantor may have or
acquire by way of subrogation, reimbursement, restitution, exoneration,
contribution or indemnity, and any similar rights (whether arising by operation
of law, by agreement or otherwise), against the Borrower arising from the
existence, payment, performance or enforcement of any of the obligations of the
Guarantor under or in connection with this Agreement, shall be subordinate in
right of payment to the Guaranteed Obligations, and the Guarantor shall not
exercise any such rights until all Guaranteed Obligations and all other
obligations under this Agreement have been paid in cash or in such other manner
as may be acceptable to the Agent and performed in full and all commitments to
extend credit under, and all Letters of Credit issued under, the Loan Documents
shall have terminated. If, notwithstanding the foregoing, any amount shall be
received by the Guarantor on account of any such rights at any time prior to the
time at which all Guaranteed Obligations and all other obligations under this
Agreement shall have been paid in cash or in such other manner as may be
acceptable to the Agent and performed in full and all commitments to extend
credit under, and all Letters of Credit issued under, the Loan Documents shall
have terminated, such amount shall be held by the Guarantor in trust for the
benefit of the Lenders, segregated from other funds held by the Guarantor, and
shall be forthwith delivered to Agent for the benefit of the Lenders in the
exact form received by the Guarantor (with any necessary endorsement), to be
applied to the Guaranteed Obligations, whether matured or unmatured, in such
order as the Agent may elect, or to be held by the Agent as security for the
Guaranteed Obligations and disposed of by the Agent in any lawful manner, all as
the Agent may elect.

            2.8   Continuing Agreement. This Agreement is a continuing guaranty
and shall continue in full force and effect until all Guaranteed Obligations and
all other amounts payable under this Agreement have been paid in cash or such
other manner as may be acceptable to the Agent and performed in full, and all
commitments to extend credit under, and all Letters of Credit issued under, the
Loan Documents have terminated, subject in any event to reinstatement

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in accordance with Section 2.4. Without limiting the generality of the
foregoing, the Guarantor hereby irrevocably waives any right to terminate or
revoke this Agreement.

                                  ARTICLE III.
                         REPRESENTATIONS AND WARRANTIES

      The Guarantor hereby represents and warrants to the Agent and the Lenders
as follows:

            3.1   Credit Agreement. The provisions of Article IV of the Credit
Agreement are hereby incorporated by reference (together with all related
definitions and cross references). The Guarantor hereby represents and warrants
to the Agent and the Lenders as provided therein.

            3.2   Representations and Warranties Remade at Each Extension of
Credit. Each request (including any deemed request) by the Borrower for any
extension of credit under any Loan Document shall be deemed to constitute a
representation and warranty by the Guarantor to the Agent and the Lenders that
the representations and warranties made by the Guarantor in this Article III are
true and correct on and as of the date of such request with the same effect as
though made on and as of such date. Failure by the Agent to receive notice from
the Guarantor to the contrary before the Lenders make any extension of credit
under any Loan Document shall constitute a further representation and warranty
by the Guarantor to the Agent and the Lenders that the representations and
warranties made by the Guarantor in this Article III are true and correct on and
as of the date of such extension of credit with the same effect as though made
on and as of such date.

                                   ARTICLE IV.
                                    COVENANTS

            4.1   Covenants Generally. Reference is hereby made to the
provisions of Articles VI and VII of the Credit Agreement (together with all
related definitions and cross references). To the extent such provisions impose
upon the Borrower a duty to cause the Guarantor (or a Subsidiary of the
Guarantor) to do or refrain from doing certain acts or things or to meet or
refrain from meeting certain conditions, the Guarantor shall (or shall cause
such Subsidiary of the Guarantor to, as the case may be) do or refrain from
doing such acts or things, or meet or refrain from meeting such conditions, as
the case may be.

                                   ARTICLE V.
                                  MISCELLANEOUS

            5.1   Amendments, etc. No amendment to or waiver of any provision of
this Agreement, and no consent to any departure by the Guarantor herefrom, shall
in any event be effective unless in a writing manually signed by or on behalf of
each Lender and the Guarantor. Any such waiver or consent shall be effective
only in the specific instance and for the specific purpose for which given.

            5.2   No Implied Waiver: Remedies Cumulative. No delay or failure of
the Agent or any Lender in exercising any right or remedy under this Agreement
shall operate as a waiver thereof; nor shall any single or partial exercise of
any such right or remedy preclude any other or further exercise thereof or the
exercise of any other right or remedy. The rights and

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remedies of the Agent and the Lenders under this Agreement are cumulative and
not exclusive of any other rights or remedies available hereunder, under any
other agreement, at law, or otherwise.

            5.3   Notices. Except to the extent, if any, otherwise expressly
provided herein, all notices and other communications (collectively, "notices")
under this Agreement shall be in writing (including facsimile transmission) and
shall be sent by certified or registered mail, by nationally-recognized
overnight courier or by personal delivery. All notices shall be sent to the
address specified in the Credit Agreement for the applicable party, or, in any
case, to such other address as shall have been designated by the applicable
party by notice to the other party hereto. Any properly given notice shall be
effective when received, except that properly given notices to the Guarantor
shall be effective at the following time, if earlier: if given by telephone,
when telephoned; if by first-class mail, three Business Days after deposit in
the mail; if by domestic overnight courier, one Business Day after pickup by
such courier; and if by facsimile transmission, upon transmission. The Agent and
the Lenders may rely on any notice (whether or not made in a manner contemplated
by this Agreement) purportedly made by or on behalf of the Guarantor, and Agent
and the Lenders shall have no duty to verify the identity or authority of the
Person giving such notice.

            5.4   Expenses. The Guarantor agrees to pay upon demand all
reasonable expenses (including reasonable fees and expenses of counsel) which
the Agent or any Lender may incur from time to time arising from or relating to
the administration of, or exercise, enforcement or preservation of rights or
remedies under, this Agreement, other than costs and expenses incurred by the
Agent or any Lender, respectively, in connection with any litigation which
results in a final, non-appealable judgment against the Agent or such Lender.

            5.5   Entire Agreement. This Agreement constitutes the entire
agreement of the parties hereto with respect to the subject matter hereof and
supersedes all prior and contemporaneous understandings and agreements.

            5.6   Survival. All representations and warranties of the Guarantor
contained in or made in connection with this Agreement shall survive, and shall
not be waived by, the execution and delivery of this Agreement, any
investigation by or knowledge of the Agent or any Lender, any extension of
credit, or any other event or circumstance whatever.

            5.7   Counterparts. This Agreement maybe executed in any number of
counterparts, including facsimile counterparts, each of which shall be deemed an
original, and all such counterparts shall constitute but one and the same
agreement.

            5.8   Setoff. In the event that any obligation of the Guarantor now
or hereafter existing under this Agreement or any other Loan Document shall have
become due and payable, after an Event of Default under the Loan Documents has
occurred, each Lender shall have the right from time to time, without notice to
the Guarantor, to set off against and apply to such due and payable amount any
obligation of any nature of each Lender to the Guarantor, including all deposits
(whether time or demand, general or special, provisionally or finally credited,
however evidenced) now or hereafter maintained by the Guarantor with the Lender.
Such right shall be absolute and unconditional in all circumstances and, without
limitation, shall exist whether such

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obligation to the Guarantor is absolute or contingent, matured or unmatured (it
being agreed that each Lender may deem such obligation to be then due and
payable at the time of such setoff), regardless of the offices or branches
through which the parties are acting with respect to the offset obligations,
regardless of whether the offset obligations are denominated in the same or
different currencies, and regardless of the existence or adequacy of any other
direct or indirect security or any other right or remedy available to such
Lender. Nothing in this Agreement or any other Loan Document shall be deemed a
waiver of or restriction on any right of setoff or banker's lien available to
any Lender under this Section 5.8, at law or otherwise. The Guarantor hereby
agrees that any affiliate of any Lender, and any holder of a participation in
any Guaranteed Obligations of the Guarantor under this Agreement, shall have the
same rights of setoff as each Lender as provided in this Section 5.8 (regardless
of whether such affiliate or participant otherwise would be deemed a creditor of
the Guarantor).

            5.9   Construction. In this Agreement, unless the context otherwise
clearly requires, references to the plural include the singular, the singular
the plural, and the part the whole; the neuter case includes the masculine and
feminine cases; and "or" is not exclusive. In this Agreement, any references to
property (or similar terms) include any interest in such property (or other item
referred to); "include," "includes," "including" and similar terms are not
limiting; and "hereof," "herein," "hereunder" and similar terms refer to this
Agreement as a whole and not to any particular provision; Section and other
headings in this Agreement, and any table of contents herein, are for reference
purposes only and shall not affect the interpretation of this Agreement in any
respect. Section and other references in this Agreement are to this Agreement
unless otherwise specified. This Agreement has been fully negotiated between the
applicable parties, each party having the benefit of legal counsel, and
accordingly neither any doctrine of construction of guaranties or suretyships in
favor of the guarantor or surety, nor any doctrine of construction of
ambiguities against the party controlling the drafting, shall apply to this
Agreement.

            5.10  Successors and Assigns. This Agreement shall be binding upon
the Guarantor, its successors and assigns, and shall inure to the benefit of and
be enforceable by the Agent, the Lender and their respective successors and
assigns. Without limitation of the foregoing, the Agent or any Lender (and any
successive assignee or transferee) from time to time may assign or otherwise
transfer all or any portion of its rights or obligations under the Loan
Documents (including all or any portion of any commitment to extend credit), or
any Guaranteed Obligations,, to any other Person, and such Guaranteed
Obligations (including any Guaranteed Obligations resulting from extension of
credit by such other Person under or in connection with the Loan Documents)
shall be and remain Guaranteed Obligations entitled to the benefit of this
Agreement, and to the extent of its interest in such Guaranteed Obligations such
other Person shall be vested with all the benefits in respect thereof granted to
the Agent or any Lender, as the case may be, in this Agreement or otherwise.

            5.11  Certain Legal Matters.

                  (a)   Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the Commonwealth of Pennsylvania,
exclusive of choice of law principles.

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                  (b)   Submission to Jurisdiction and Venue: Consent to Service
of Process: Waiver of Jury Trial: Etc. The Guarantor hereby irrevocably and
unconditionally:

                        (i)   agrees that any action, suit or proceeding by any
                  Person arising from or relating to this Agreement or any other
                  Loan Document or any statement, course of conduct, act,
                  omission or event in connection with any of the foregoing
                  (collectively, "Related Litigation') may be brought in any
                  state or federal court of competent jurisdiction sitting in
                  Allegheny County, Pennsylvania, submits to the jurisdiction of
                  such courts, and agrees not to bring any Related Litigation in
                  any other forum (but nothing herein shall affect the right of
                  the Agent or any Lender to bring any Related Litigation in any
                  other forum);

                        (ii)  acknowledges that such courts will be the most
                  convenient forum for any Related Litigation, waives any
                  objection to the laying of venue of any Related Litigation
                  brought in any such court, waives any claim that any Related
                  Litigation brought in any such court has been brought in an
                  inconvenient forum, and waives any right to object, with
                  respect to any Related Litigation, that such court does not
                  have jurisdiction over it;

                        (iii) consents and agrees to service of any summons,
                  complaint or other legal process in any Related Litigation by
                  registered or certified U.S. mail, postage prepaid, to it at
                  the address for notices described in this Agreement, and
                  consents and agrees that such service shall constitute in
                  every respect valid and effective service (but nothing herein
                  shall affect the validity or effectiveness of process served
                  in any other manner permitted by law); and

                        (iv)  waives the right to trial by jury in any Related
                  Litigation.

                  (c)   Limitation of Liability. No claim may be made by the
Guarantor against the Agent or any Lender or any affiliate, director, officer,
employee, attorney or agent of the Agent or any Lender for any special,
indirect, consequential or punitive damages in respect of any claim arising from
or relating to this Agreement or any other Loan Document or any statement,
course of conduct, act, omission or event in connection with any of the
foregoing (whether based on breach of contract, tort or any other theory of
liability); and the Guarantor hereby waives, releases and agrees not to sue upon
any claim for any such damages, whether or not accrued and whether or not known
or suspected to exist.

      The Guarantor acknowledges that it has been represented by legal counsel
in connection with the execution and delivery of this Agreement and that it
understands the provisions of this Agreement.

                          [SIGNATURE ON FOLLOWING PAGE]

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                    SIGNATURE PAGE 1 OF 1 TO PARENT GUARANTY

      IN WITNESS WHEREOF, the Guarantor has executed and delivered this
Agreement as of the date first above written.

                                                 BLACK BOX CORPORATION

                                                 By: ___________________________
                                                 Name: _________________________
                                                 Title: ________________________

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